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141.
1. Thirty adult female pigeons (Columba livia domestica) were randomly divided into 3 equal groups; the 1st and 2nd groups were immunised with bovine serum albumin (BSA) at 0 and 20 d, the 2nd group also received 1 g L-carnitine per litre of drinking water from -5 to 25 d post-immunisation (dpi) and the 3rd group, a control group, received neither treatment. 2. Body weights and serum samples were taken at 0, 5, 10, 15, 20, 25, 30 and 35 dpi. 3. Both BSA-specific IgG and IgM responses were enhanced by about 10% by L-carnitine supplementation. 4. L-carnitine supplemented pigeons showed a higher water consumption. Body weight loss during the onset of the immune response showed a slight tendency to be counteracted by L-carnitine supplementation. 5. The impact of L-carnitine on resistance and resilience to an immunological challenge is discussed.  相似文献   
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The aim of this study was to investigate the effects of a porcine reproductive and respiratory syndrome virus (PRRSV) infection on the development of the immune response after pseudorabies virus (PRV) vaccination in pigs. Pigs were intranasally inoculated with the European PRRSV strain, Lelystad virus ter Huurne, and were vaccinated intramuscularly with PRV 2 weeks later (LV-PRV group). Control pigs were vaccinated with PRV only (PRV group). Eight weeks after PRV vaccination, pigs from both groups were challenged intranasally with wild-type PRV. We measured the lymphoproliferative, and the cytolytic responses to PRV of peripheral blood mononuclear cells (PBMC), isolated from blood samples. In addition, serum samples were examined for antibodies against PRV and LV. One week after PRV vaccination, PBMC proliferated abundantly to PRV in both groups. However, in the LV-PRV group the lymphoproliferative response declined after 1 week, whereas, in the PRV group, the lymphoproliferative response was high for 3 weeks and declined thereafter (P<0.05). After challenge, the lymphoproliferative response was 1 week earlier and was consistently and significantly higher in the PRV group than in the LV-PRV group. The PRV-specific killing was higher at 3 weeks after PRV vaccination and 5 weeks after PRV challenge 19+/-3 and 24+/-6%, respectively, in the PRV group, compared to 7+/-4 and 6+/-9%, respectively, in the LV-PRV group (P<0.05). However, later after vaccination and challenge the cytolytic response was identical in both groups. The antibody titre against PRV developed equally in both groups. After challenge, no PRV virus was isolated from both groups. From these results we conclude that, although PRRSV infection did cause changes in the time course of the T-lymphocyte response after PRV vaccination, PRRSV infection did not inhibit the development of vaccine-induced protection after PRV.  相似文献   
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A comparative study of antibody production was carried out using BALB/c mice immunized with 20 or 50microg vesicular fluid (VF)-Tcra (Taenia crassiceps) antigens, and gel of <30kD or eluate from <30kD peptides. Good IgM, IgA and IgG levels were detected by ELISA-Tcra and the antibodies presented reactivity with the <20kD peptides when tested by immunoblotting-Tcra. The antibodies from animals immunized with 20 and 50microg presented high anti-Tso cross-reactivity in ELISA (IgG>IgM and IgA). All groups presented IgG antibodies identifying the 12kD Tso-peptide.  相似文献   
147.
ABSTRACT The biochemical basis of tolerance in banana to Fusarium wilt, caused by the pathogen Fusarium oxysporum f. sp. cubense race four, was investigated. Tissue culture banana plants from tolerant cv. Goldfinger and susceptible cv. Williams were maintained in a hydroponic system and inoculated with conidial suspensions to evaluate the degree of tolerance to susceptibility between the two clones and to investigate the effectiveness of this technique as a potential tool for early screening for resistance in breeding programs. Similarly, defense responses were induced by treatment of the plants with an elicitor preparation from the mycelial cell walls of the pathogen. Differences in the induction of lignin and callose deposition, phenolics, and the enzymes involved in cell wall strengthening; phenylalanine ammonia lyase, cinnamyl alcohol dehydrogenase, peroxidase, and polyphenol oxidase were determined. Root tissue of the tolerant cv. Goldfinger responded to the fungal elicitor through the strong deposition of lignin, preceded by the induction or activation of the enzyme activities involved in the synthesis and polymerization thereof, whereas only slight increases were observed for the susceptible cv. Williams. No increase in callose content was observed for either clone. These results indicate an important role for cell wall strengthening due to the deposition of lignin as an inducible defense mechanism of banana roots against F. oxysporum f. sp. cubense race four.  相似文献   
148.
解决学校培养出的人才不是企业急需人才这个矛盾的方法。就是要以市场需求为导向,以学生成才为目标进行教学改革,确定教学体系,实行以岗位定课程的订单式教学法,企业与学校紧密结合。学校根据企业所需要的员工应具备的知识为框架组织教学,同绕思想教育体系、技能技巧体系、专业能力体系进行教学设计,对学校、教师及学生都提出了更高的要求。  相似文献   
149.
An 8-year-old, entire male crossbreed dog had a 2-day history of abdominal pain and straining to urinate and defecate. A diagnosis of urolithiasis with urinary retention, and probable prostatitis was made. The dog was treated with fluids and enrofloxacin. Five days later, ultrasonography of the prostate showed two hypoechoic areas compatible with abscesses. Twelve hours later, the patient started to urinate from the rectum during micturition and urethrorectal fistula was diagnosed. The omentalization of the prostatic abscesses and castration were performed and calculi were removed. The urethrorectal fistula was treated conservatively with an indwelling urinary catheter, a low residue diet and antibiotics. The dog recovered uneventfully without recurrence of the fistula.  相似文献   
150.
Basic characteristics of European bison (Bison bonasus) semen were described and the efficacies of two extenders-Triladyl, containing egg yolk, and a synthetic extender, containing soybean lipids-were tested for semen cryopreservation. Seven ejaculates were collected by electroejaculation from a 10-yr-old, European bison bull. Each ejaculate was diluted at 37 degrees C to a final concentration of 200 x 10(6) sperm/ml with Triladyl or the synthetic extender. Extended semen samples were frozen according to a standard bull semen freezing protocol. After 2 wk of storage, one straw from each extender and ejaculate was thawed, and postthaw quality was evaluated by individual sperm motility and movement rate, numbers of sperm morphologic abnormalities and intact acrosomes, functional integrity of the sperm membranes determined by hypoosmotic swelling test (HOST), viability (live-dead, eosin-nigrosin stain), and a heterologous in vitro sperm penetration assay (SPA). A total of 600 in vitro-matured bovine oocytes were inseminated with 1 X 10(6) spermatozoa of Holstein semen frozen-thawed in Triladyl (control) or of European bison semen frozen in Triladyl or the synthetic extender. Nuclear status of the oocytes was determined after 18 h of sperm-oocyte coincubation. Extender had no effect on any evaluated parameters of semen after dilution and cooling (4 hr at 5 degrees C) or in postthaw individual motility, quality of movement, and sperm morphology. However, significantly (P < 0.05) higher numbers of spermatozoa with intact acrosomes, intact membranes (HOST), and viable sperm (P < 0.01) were in semen frozen in Triladyl than in the synthetic extender. Mean values for heterologous SPA for bull (control) and for bison semen frozen in the synthetic extender were very much alike-63.3+/-10.6% and 63.1 +/- 15.9%, respectively; bison semen frozen in Triladyl was lower, 43.0+/-24.2% but not significantly different. Cumulative results from a variety of viability assays of diluted/cooled and frozen-thawed semen, including the heterologous SPA, suggest that European bison semen can be successfully frozen in both extenders tested in this study.  相似文献   
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